Exploring Life Science Chapter 8
Plants
Chapter 8 – Plants
Engage: Gymno = Naked
Objectives:
1. Identify the characteristics of Gymnosperms &
Angiosperms and describe how they reproduce.
2. Explain how Angiosperms reproduce.
3. Describe the 2 types of Angiosperms.
8-4 : Gymnosperm & Angiosperms
A. Introduction
1. Gymnosperms -- 360 million years.
2. Angiosperms -- 100 million years.
B. Gymnosperms – Naked seeds – (No fruit – Ovary)
1. Groups (phyla)
a. Cycads
b. Ginkgoes
c. Conifers
d. Gnetophytes
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Exploring Life Science Chapter 8
Plants
2. Cycads – 175 million years ago most plants.
a. Tropical
b. Look like palm trees with cones.
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Exploring Life Science Chapter 8
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3. Ginkgoes
a. Common-dinosaur-age
b. Maidenhair tree
c. None grow in wild
d. Male & female trees
4. Conifers
a. 550 species
b. Redwoods & Sequoias -- tallest trees
c. Bristle cone pines -- longest living trees.
d. “Cone-Bearer”
e. Most evergreens
except larches & bald cypresses
f. Uses: wood, turpentine, pitch, rosin.
Juniper seeds -- flavor food
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Exploring Life Science Chapter 8
Plants
taxol - found in bark of pacific yew tree,
treatment of cancer.
5. Gnetophytes
a. Found in hot deserts & tropical rain forests.
b. Climbing tropical vines,
Shrubs or Trees
c. Welwitschia – live to be 1000 years old.
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C. Reproduction of Gymnosperms
1. Cones – reproductive structure.(Ponderosa Pine)
2. Steps
Pollination – Pollen lands on Ovule.
Fertilization – Sperm & Egg join.
Seed Development
Seed Dispersal
Germination
D. Angiosperms
1. 230,000 species
2. Found almost everywhere
3. “Flowering Plants”
4. Flowers - Structures that contain the
reproductive organs.( Rafflesia)
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Exploring Life Science Chapter 8
Plants
a. Structure
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Exploring Life Science Chapter 8
Plants
Sepals – Leaf-like encloses bud protects dev.
flower.
Petals – Leaf-like colorful structure colors,
shapes & odors attract insects & other animals.
Stamens - Male organs.
Filament - Stalk of stamens.
Anther – Knob-like part of stamen
produces pollen.
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Exploring Life Science Chapter 8
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Pistils - Female organs (center of flower)
Stigma - Sticky top of pistil.
Style - Slender tube.
Ovary - Contains 1 or more ovules.
E. Reproduction in Angiosperms
5. Pollination
a. Pollen lands on stigma
- wall of pollen breaks open
- tube grows down style into ovule
- sperm cell fertilizes egg cell in ovule.
b. Methods - wind, insects, birds & other
animals.
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Exploring Life Science Chapter 8
Plants
6. Steps
Pollination
Fertilization
Seed Development
Ovary around seed (Fruit) – ripened ovary.
some fruit - apples, cherries, cucumbers
& tomatoes.
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Plants
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